Question

The area of the parallelogram whose diagonals are `vec(P)= 2hat(i)+3hat(j)` and `vec(Q)= hat(i)+4hat(j)`is
A. 5 square units
B. 10 square units
C. 20 square units
D. 2.5 square units

Answer 1

Correct Answer - D
`Area= 1/2|vec(P)xxvec(Q)|=|1/2||(hat(i),hat(j),hat(k)),(2,3,0),(1,4,0)|`
`=|1/2[2xx4-3xx1]hat(k)|=5/2`